Pipe function

Pipe() function is the light-weight version of Pipe operator yet has more features.

1. Support all features of %>>% but use $ for command chaining
2. Support direct subsetting, extraction, element assignment

Basically, Pipe() creates a Pipe object for which $ is specially defined to perform first-argument piping, and .(...) is defined to act like x %>>% (...). Pipe object also supports subsetting ([]), extraction ([[]]), and their corresponding assignment operations.

Using Pipe() the following code

mtcars %>>%
  lm(formula = mpg ~ wt + cyl) %>>%
  summary

can be rewritten like

Pipe(mtcars)$
  lm(formula = mpg ~ wt + cyl)$
  summary()